Project Summary The overall objective in the proposed project is to develop and test a prototype Cyanalyzer sensor designed for the rapid and accurate diagnosis of cyanide exposure. The proposed device directly addresses a long-term goal of the National Institute of Neurological Disorders and Stroke/NIH Countermeasures Against Chemical Threats (CounterACT) program: development of ?rapid diagnostic tests and assays to identify biological markers consistent with cyanide exposure and the level of exposure.? Phase I equivalent research demonstrated that the current laboratory-based Cyanalyzer prototype meets or exceeds each requirement necessary for rapid and accurate on-site cyanide diagnosis: currently 100% diagnostic accuracy based a standard animal model of cyanide exposure (N=37 samples; 10 rabbits, each with one blank/non-exposed and 2-3 cyanide exposed samples); rapid analysis time (60 s); sensitivity (the limit of detection ? 5 ?M ? is well below the threshold of ?exposure? ? 15 ?M ? which was set based on the maximum reported blood cyanide concentrations of smokers); small sample volume (25 ?L); selectivity, precision (<12% relative standard deviation); and accuracy (10015%). During this Direct to Phase II SBIR project, Seacoast Science, Inc. (SSI), in collaboration with South Dakota State University (SDSU), the University of California, Irvine (UCI), and the Midwest Research Institute (MRI) propose carrying the Cyanalyzer from a research stage comprehensive analytical tool to advanced prototype development, animal trials, and completion of sufficient production units for a follow-on multisite clinical trial. The following specific aims are proposed to accomplish this objective: 1. Design and production of an optimized prototype of the academic cyanide diagnostic sensor (10 units); 2. Method validation, laboratory testing, animal testing (rabbit (UCI) and mouse (MRI)), and analytical confirmation of the optimized prototype; and 3. Incorporation of lessons learned from specific aim 2, scale-up, and initial production of approximately 100 Cyanalyzer units for future multi-site Phase III clinical trials. Throughout all tasks, Seacoast Science and SDSU will work with a FDA consulting firm to insure that appropriate steps are met to meet regulatory requirements necessary for device sales.